H.264 is an industry standard for video compression, the process of converting digital video into a format that takes up less capacity when it is stored or bandwidth when transmitted. Video compression (or video coding) is a technology incorporated in applications such as digital television, DVD-Video, mobile TV, videoconferencing and Internet video streaming, among others. An encoder converts video into a compressed format and a decoder converts compressed video back into an uncompressed format. Standardizing video compression makes it possible for products from different manufacturers (e.g. encoders, decoders and storage media) to inter-operate.
Recommendation H.264: Advanced Video Coding is a document published by the international standards bodies ITU-T (International Telecommunication Union) and ISO/IEC (International Organization for Standardization/International Electrotechnical Commission). It defines a format (syntax) for compressed video and a method for decoding this syntax to produce a displayable video sequence. The standard document does not actually specify how to encode (compress) digital video—this is left to the manufacturer of a video encoder—but in practice the encoder is likely to mirror the steps of the decoding process.
The H.264/AVC standard was first published in 2003. It builds on the concepts of earlier standards such as MPEG-2 and MPEG-4 Visual and offers the potential for better compression efficiency (i.e. better-quality compressed video) and greater flexibility m compressing, transmitting and storing video.